The History of Observation

a look at the role of observation and experimentation in science

The GreeksPLATO (428-347 BC)

• reality is abstract “ideal forms”, vs. “shadows” that are physcially observed– role of observation is deductive: leading away from big ideas to see how the details work out in the real world

– knowledge is tested by argument and logic (not experimentation)

ARISTOTLE (384-322 BC)• reality is the observed physical world, ideal forms are only useful constructs– role of observation becomes somewhat inductive: observations leading from observations towards patterns & big ideas

– There is still mostly deduction

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ARISTOTLE

Scholastics (A.D. 1200’s)

•knowledge is based on accepted authority, not observations / experiments

•The first accepted authorities were scriptures, then also rediscovered Greeks, especially Aristotle

•knowledge is tested by argument and logic (look up the “trivium” of medieval universities!)

Empiricists

ROGER BACON (c. AD 1214-1292)• backlash against scholastics (some the book facts were wrong!)

• experience is superior to argument• experimental science as a valid route to truth: observation is key

FRANCIS BACON (AD 1561-1626)RENE DESCARTES (1591-1650)

• extreme empiricism: science should be purely inductive• science proceeds as we build up facts into proven theories

• quality obs. are facts unbiased by prior knowledge (idea of “objectivity”)

• “Cogito ergo sum” and interest in reduction of big ideas to mathematical principles

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Constructivists

KARL POPPER (1902-1996)• observations are context-bound & theory-driven: they will always depend on what the observer already knows

• role of observation is to test theories (ideas)

• science proceeds when– theories are proven false and we have to reconstruct what we know (revolutionary science)

– we reaffirm, extend and apply useful theories (normal science)

• theories are created “constructs”, not absolute truth induced from observation

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